Method of making coreless golf balls



May 11, 1943.

D. G. SLOVIN METHOD OF MAKING CORELESS GOLF BALLS Filed Dec. 3, 1940 INVENTOR.

Patented May 11, 1943 David George Slovin, Providence, R. 1., United States Rubber Company,

assignor to New York,

N. Y., a corporation of New Jersey 7 Application December 3, 1940, Serial No. 368,282

10 Claims.

This invention relates to a method of making golf balls, and more particularly coreless balls.

For many years, golf balls have been made with a body portion of tense wound rubber thread or tape, disposed on a winding core, and in the case of the 'more expensive balls they have in later years been provided with a core or center in the form of a flexible receptacle containing a liquid or pasty material. More recently there has'been some demand for a coreless ball. A coreless ball in itself is quite old in the art, but in earlier examples it was necessary for the operator to bunch up some of the rubber thread or otherwise form a nucleus of it and manually wind on the thread until a size had been reached suflicient to permit placing it in a winding machine, and it is obvious that this method was slow and laborious. It has also been attempted to wind the thread without the use of a core and entirely by winding machine, but this has necessitated the use of special machines.

By the present invention a coreless ball can be produced without the necessity of using any other than the present equipment for balls with liquid centers, and after a ball has been wound on a receptacle containing liquid or liquefiable material, the material is withdrawn from the receptacle, thereby permitting it to collapse and partially relaxing the inner windings of thread so as to produce a coreless ball.

An object of the present invention is to provide a simple, improved method of making coreless golf balls and which need not require additional equipment over that now used.

Other objects will appear from the specification and drawing, in which latter Figure 1 is a sectional view of a golf ball at one stage of the method,

Figure 2 is a similar section showing an inserted hypodermic needle for removing the liquid center, and

Figure 3 is a section of a finished ball.

In carrying out the method a bag I of rubber or other suitable material is provided which, if desired, may be made by molding two hemispherical cups, uniting them, and filling the bag or receptacle thus formed with any suitable liquid 2 which may be readily solidified. The liquid may be introduced by means of a hypodermic needle. Instead of thus filling the center with a liquid the hemi-spherical halves of the bag may be joined around a solid center formed of material or materials which will liquefy of their own accord at ordinary temperatures or slightly elevated temperatures. It is preferred however to make the bag I on a form by the dipping method using either a rubber cement or an aqueous dispersion of rubber such as latex, which need not be fully vulcanized or vulcanized at all. Bags or other receptacles can thus be made of much less thickness than is practicable by the usual molding procedure and therefore more readily collapsed, and occupying much less space. Any other suitable material than rubber may be used if desired. When the bag I is made by the dipping method it is ordinarily provided with a small neck through which the filling liquid can be introduced, after which the neck is tied off.

The center thus produced, if containing a liquid, is then frozen and wound on the usual types of winding machines with tense rubber thread 3 or with both rubber tape and thread. After completing the winding the ball is then allowed to stand until the contents of the center are liquefied, and in the case where these contents are of a solid easily liquefiable material, it may be desirable to apply some warmth to hasten the liquefaction. After the material 2 in the center has been liquefied a hypodermic needle 4 is inserted through the windings and the Wall of the bag I, and the'liquid 2 is withdrawn. By reason of the withdrawal of the liquid and the heavy pressure from the tense windings of the thread the bag I is collapsed and the inner adjacent windings 3' of the thread are partially relaxed so that the space formerly occupied by the liquid 2 is filled.

If desired, the inner windings when applied to the center may be at a much greater tension than the outer ones. Also in place of inserting the hypodermic needle through the wound center, this operation may be performed after the cover 5 has been molded on the ball. The ball, after the withdrawal of the liquid 2 and the application of the cover, is finished in the usual manner.

It will be seen that by thev invention a method has been provided for making a coreless ball which is simple and requires no special equipment other than that previously used in making liquid center golf balls.

Having thus shown and described my invention, what I claim and desire to protect by Letters Patent is:

1. The method of making a golf ball which comprises, winding layers of tense elastic material about a collapsible receptacle filled with a material that is convertible to a liquid form and hypodermically withdrawing the filling in fluid form and so that it does not contact the windings, thereby permitting collapse of said receptacle and partial relaxation of the inner windings of tense elastic material.

2 The method of making a golf ball which comprises the steps of winding layers of tense rubber around a closed collapsible sack while filled with liquefiable material in solid form, liquefying said material, and hypodermically withdrawing said material so that it does not contact the windings, thereby permitting collapse of said sack and partial relaxation of the inner tense rubber windings.

3. The method of making a golf ball which comprises the steps of winding layers of tense rubber thread around a closed collapsible rubber sack while filled with liquefiable material in solid form, liquefying said material, hypodermically withdrawing said material so that it does not contact the windings, thereby permitting collapse of said sack and partial relexation of the inner tense rubber thread windings, and finishing the ball.

4. The method of making a golf ball which comprises filling a collapsible sack with liquid, solidifying said liquid, applying windings of tense rubber around said sack, reliquefying the sack contents, hypodermically withdrawing the liquid through said windings so that it does not contact the windings, and finishing the ball.

5. The method of making a golf ball which comprises filling a relatively thin walled flexible rubber receptacle with liquid, solidifying said liquid, applying windings of tense rubber around said receptacle, reliquefying the receptacle contents, hypodermically withdrawing the liquid through said windings so that it does not contact the windings to thereby permit collapse of said receptacle and partial relaxation of the inner tense rubber windings, and applying a cover.

6. In the manufacture of winding centers for playing balls, the method which comprises filling a container with liquid, freezing to provide a solid windin element, winding elastic thread under tension upon said winding element, rupturing the container and liquefying the frozen liquid and permitting it to escape through and from the winding and the winding to contract and collapse the container therein and the space formerly occupied by the liquid to be taken up by the collapsed container and the tensioned threads.

7. In the manufacture of playing balls, the method which comprises filling a collapsible elastic container with liquid, freezing to provide a solid winding element, winding elastic threads under tension upon said winding element, liquefying the frozen liquid, and causing it to escape from the container and the winding and the latter to contract and collapse the container therein and the space formerly occupied by the liquid to be taken up by the collapsed container and the tensioned threads.

8. In the manufacture of playing balls, the method which comprises filling a collapsible container with a fluid capable of being solidified by freezing, freezing the filled container to provide a solid winding element, winding elastic strands under tension upon said winding element, and fiuidifying the frozen fluid and causing it to escape from the container and the Winding and the latter to contract and collapse the container and the space formerly occupied by the fluid to be taken up by the collapsed container and the tensioned strands.

9. The method of making playing balls comprising filling a spherical elastic container with a fluid capable of being solidified by freezing, freezing the filled container, Winding rubber strands around the pellet thus produced under substantial tension to provide a layer of substantial thickness of wound strands, fiuidifying the frozen fluid, puncturing the container, and permitting the fluid to escape from the container and the winding and the winding to contract and collapse the container centrally within the contracted winding.

10. The method of making a golf ball which comprises filling a relatively thin walled flexible receptacle with liquid, applying windings of tense rubber around said receptacle, hypodermically withdrawing the liquid through said windings so that it does not contact the windings to thereby permit collapse of said receptacle and partial relaxation of the inner tense rubber windings, and finishing the ball.

DAVID GEORGE SLOVIN. 

